Implementation of a tunable RGB LED light source

There have been a lot of advancements in the luminaire technology which has resulted in the popularity of LED's (Light Emitting Diode). These light emitting diodes are being used almost everywhere mainly because of their high efficacy and possibility of controlling color. Any color can be produced by proper mixing of Red-Green-Blue LEDs. This paper, proposes the technique of generating different CCTs of white light located on the planckian locus of CIE 1931 by varying the driving current of a luminaire. This is done by Hardware in loop simulation using NI LabVIEW that takes the user preference and accordingly regulates the light output by providing the required control signals to the DAQ. This system uses DAQ to generate the PWM signals according to the mixing proportions thereby eliminating the need of microcontrollers. Switch mode power converters behave as a constant current source for the RGB LED luminaire. The implemented RGB LED light source that is dynamically tunable can be a good lighting fixture for mood lighting in hotels, entertainment halls, shops etc.